Running coupling BFKL equation and deep inelastic scattering

✍ Scribed by R.S. Thorne

• Book ID: 104356033
• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 260 KB
• Volume: 79
• Category: Article
• ISSN: 0920-5632
• DOI: 10.1016/s0920-5632(99)00678-7

✦ Synopsis

I examine the form of the solution of the BFKL equation with running coupling relevant for deep inelastic scattering. The evolution of structure functions is precisely determined and well described by an effective coupling ,~ 1/(3o(ln(Q2/A ~) + 3.6(a~(Q 2) ln(1/x)) 1/2) (until extremely small x). Corrections to the LO equation are relatively small, and the perturbative expansion is stable. Comparison to data via a global fit is very successful. Small x physics has recently been a particular area of both experimental and theoretical interest. The first data on structure functions at very small values of x (down to x = 10 -5 ) obtained by HERA [1,2] have themselves been enough to make this an active topic. However, the fact that the splitting functions and coefficient functions required for the construction of structure functions have expansions containing terms an(# 2) lnn-l(1/x) has added extra impetus, implying that at small x one may have to account for leading terms in In(l/x) at high orders in as, rather than just expand naively in powers of as.